A record number of startups transformed into unicorns in the second quarter.

The valuation of 24 startups soared past the $1 billion mark, more than double (120%) the 11 reaching that level in the first quarter of the year, according to data from research firm CB Insights. The most recent companies to join the billion-dollar club include Zenefits, maker of human resources software; Oscar Health Insurance; and enterprise software company MarkLogic.